Editor's Note: (Sir Andrew Wood is a former British ambassador to Moscow. His is an associate fellow of Chatham House's Russia and Eurasia program. The opinions in this article belong to the author.)
(CNN) The second discussion in as many days between US President Donald Trump and Russian President Vladimir Putin at the G20 meeting over dinner in Hamburg was bound to give rise to a great deal of speculation.
The two sides have already given differing accounts of what had been said at their first and more formal meeting -- though both indicated that they were committed to greater cooperation with one another.
At the leaders' second meeting, there was only a Russian translator present when the two broke away from the main group to talk. Trump, who was due to sit near Japanese leader Shinzo Abe and his wife during the meal, opted to bring a translator who spoke Japanese.
What this ultimately means is that the Kremlin will decide what is publicly said about the meeting, and as a result it gets to determine the narrative of its fallout.
We do not know what it was that prompted President Trump to go over to talk to Putin on the second occasion for what sound like a relatively long conversation.
But the supposition must be that what transpired was rather more than an exchange designed merely to underpin the relationship that Trump had hoped he had established at their first meeting.
If either President Trump or Putin had something to say about Ukraine, for instance, one must suppose -- or at least hope -- that Trump spoke with US Secretary of State Tillerson about it before the latter met with Ukrainian President Petro Poroshenko in Kiev.
There is nothing inherently unusual in Trump taking advantage of a dinner to speak with Putin. But if he had planned to offer more than a gesture then it would have been normal to ensure that he had access to his own translator -- and for him to give an account of what had been discussed to close allies, as well as members of his own administration.
The gesture itself was a signal of his continuing desire to establish a good personal relationship with Putin. By now, Trump must realize that the last several months have made that more difficult than he might have initially expected or hoped.
But in discussion, one thing tends to lead to another. It is therefore only natural that a number of interested parties are now wondering what that might have been said -- and in many cases will find their answers to that question profoundly troubling.
It would presumably also have occurred to both presidents that the media would take a considerable interest in exploring the possibilities.
Considering this, even if the meeting turns out to be nothing more than a slip in Trump's judgment, the fact that he has once given the Russians the opportunity to take control of the facts is concerning (see also his meeting with Russia's ambassador to the US, where he denied access to US media only to have Russian state media publish pictures of the meeting later on).
At this stage in his presidency -- and aware as he obviously is of the Russia question surrounding his administration -- that Trump did something which can so easily be interpreted as a matter of real concern is at best rash and irresponsible.